should I change my password as soon as possible or is it okay to leave it? (I hate having to memorize another password)
By all means change your password, but change it to something completely random including special characters. Anything you can remember is unlikely to be random and is easily cracked if an attacker has the additional salt information that was stolen during the last hack.
If your new password is not completely random and a similar hack happens in the future your password could be cracked and you could lose your account. Consider using password management software to generate and store a new password.